Driven-headed fastening



am un VERNON L. LEVNGSTGIJ', OF LAKE CHARLES, LOSIANA.

DREVEN-HEADED FASTENNG.

Application led June 7, 1921.

To @ZZ whom t may concern Be it lrnown that l, VERNON L. Levine- STON, a citizen of the United States, residingo at Lake Charles, in the Parish of Calcasieu and State of Louisiana, have invented certain new and useful limprovements in lriven- Headed Fastenings, of whicl'i the following is a specification.

The invention relates to improvements in nails or other forms of similar fastenings c adapted to be driven to operative position.

. operative The principal object of the invention is to provide for a fastening of the char eter described, and one embodying a locking means effective, upon the final driving movements, 1Lo securely retain the fastening in its position against displacement` through accident, or, for all practical purposes, against ordinary attempts for its withdrawal or removal from locked position.

Another object of the invention is to provide for a driven fastening of the type mentioned, and one wherein tie locking means is integrally formed with the fastening, and is of a nature and arrangement whereby to not increase the present cost manufacture of such devices to an appreciable amount.

l/Vith the foregoing and other objects in view, the invention resides in the 'certain novel and useful construction and arrangement as will be hereinafter more fully described, set forth in the appended claims. and illustrated in the accompanying drawing, in which,

Figure l is an elevation of the preferred embodiment thereof,

Fig. 2 is a section taken on line 2 2 of F ig. l, and,

Fig. 3 is a similar view taken on the line 3---3 of Fig. 1.

Referring to the drawing, the numeral Ll) indicates the body portion or shank of a nail form of fastening; l1 the pointed end of the sameand 12 the driving head ziereof. `Formed radially of the body 10 a slip distance inwardly from 'the lower pointed end ll, is a tapering lug or projection i3 which is circular in plan and having a scuared upper end, forming the positive locking means of the device, and which formed to provide a flat horizontally dis- Serial No. 475,769.

posed upper face, and a downwardly and inwardly inclined outer or lower face, the latter face being provided to decrease the resistance of the lug or projection 13 to the driven movement of the body l0 into the work. Formed on the body l0, downwardly frm a point immediately or slightly below the driving head l2, is a spiral rib oir screw thread le, which is adapted to impart to the body l0 more than a half revolution, or less, of turning movement in the work, during the Final driving of the device, the lower end of the rib or thread la bei ing preferably of a substantial knife edge formation whereby to facilitate the final driving movement the body, and to further decrease the resistance offered to such driving movement.

ln the driving of the fastening thus provided, the lug er proiection 13 enters the work during the initial driven movement of the body i0., and passes straight down-- ward with the latter until the lower sharpened end 1.4;', of the rib or thread 14, en` ters the work, when upon further driving movement to the body l0, a turning movement will be iuiiiarted to the same and will continue for slightly more than a half revolution, during the final driving movement of the body, whereby the lug or projection 13 will move in a spiral path of a sharper pitch tha that of the rib or thread lll, and until the device is fully driven home. When finally driven home in the work, the nail or other similar fastening will he securely hold against any and all ordinary attempt for its withdrawal and removal from position, and will otherwise effectively maintain its operative position throughout its period of continued use in the work.

lt is well understood that the device may be made in any of the usual and ordinary forms of driven headed fastenings without O'ard to size or configuration, other than as shown, without departing from the spiri of the invention or the scope of the claim appended hereto.

Having thus fully described the invention, what is claimed is' A driven headed fastening including a body portion, a worl; penetrating lug formed on the body portion and having a downwardly and inwardly inclined face for decreasing the resistance offered thereby to the driven movement of the body7 seid lug being circular in plan and having a squared upper end and :L spiral rib formed on the body above the extension for imparting e turning movement to the body portion `and said extension during the driving operation` the inner end of said spiral rib being of a. knife edge formation whereby to reduce the resistance thereof to the driven movei ments, as aforesaid.

In testimony whereof, aix my signuture hereto.

VERNON L. LEVNGSTON. 

